The Mute Swan has the most southerly breeding range of the Eurasian swans. Many birds live in areas that are mild enough for them not to have to migrate during the non-breeding season. The species is patchily distributed but locally common across temperate regions of the Palearctic, from western to northeast Europe. It breeds widely in western and central Europe and more locally in southeast Europe, the Black Sea and Caspian regions and central Asia. In winter it occurs south to the Mediterranean Sea and the southern shores of the Caspian Sea.

Seven populations throughout Europe and Asia are currently recognised by Wetlands International including the largely sedentary British and Irish populations that are the subject of this review. The winter distribution is broadly similar to the breeding distribution, except for localised movements to coastal waters, especially in cold weather, and to freshwater marshes and agricultural fields.

The British population remained fairly stable from the late 1960s to the mid-1980s; since the late 1980s there has been a large increase in population size. The Irish population increased in size between the 1970s and mid-1980s, but has stabilised since. The British population is currently estimated at 37,500 and the Irish population is estimated at 10,000 birds.